Field
Embodiments relate to photovoltaic (PV) modules and photovoltaic module manufacturing processes.
Technical Background
Photovoltaic modules are used to convert sunlight into electricity. Two major types used or in development today are wafered modules using multiple silicon wafers (“wafered modules” or “wafered silicon modules” or “wafered silicon devices”—all terms that can be used interchangably) connected together and thin film modules using cadmium telluride (CdTe), copper indium gallium di-selenide (CIGS) or thin film (amorphous and microcrystalline) silicon. Typical packages 100 for the wafered modules have one protective glass layer 10 such as a soda lime glass, a polymer back sheet 12, silicon wafers 16 and encapsulant layers 20 between the protective glass layer and the back sheet, and optionally, an edge seal 18, a metal frame 14, and electrical contacts 22 as shown by the cross section in FIG. 1A. Typical packages 101 for thin film modules have two protective glass layers 10 such as soda lime, a thin film(s) 17, an encapsulant layer 20 between the two glass sheets, an edge seal 18, and electrical contacts 22 as shown by the cross section in FIG. 1B. Ethylene vinyl acetate (EVA), polyvinyl butyral (PVB) or other encapsulants are commonly used to bond the two sheets together. Sealing materials such as a butyl sealant at the module perimeters are used to increase moisture resistance.
There is a continuing drive to make PV technology competitive with existing power production methods, e.g., hydro, coal, nuclear, wind, etc., in the power generation industry. To do so, manufacturing costs, conversion efficiency, and efficiency degradation are some of the design challenges that need to be addressed.